System and method for growing a plant in an at least partly conditioned environment

Abstract

A system for growing a plant (1) in an at least partly conditioned environment includes a cultivation base (11) for receiving a culture substrate (3) with a root system (4) of the plant therein. Root temperature control elements (12) are provided which are able and adapted to impose a predetermined root temperature on the root system, and lighting elements (20,21,22) which are able and adapted to expose leaves of the plant to actinic artificial light. Leaf heating elements are also provided, which are able and adapted to impose on the leaf of the plant a leaf temperature varying from an ambient temperature. In a method for growing the plant a carbon dioxide assimilation management of a leaf system of the plant is thus influenced, and a supply of actinic light, the root temperature and the carbon dioxide assimilation management are adapted to each other.

Description

BACKGROUND OF THE INVENTIONField of the Invention[0001]The present invention relates to a system for growing a plant in an at least partly conditioned environment, comprising a cultivation base for receiving a culture substrate with a root system of the plant therein, root temperature control means which are able and adapted to impose a predetermined root temperature on the root system, and comprising lighting means which are able and adapted to expose leaves of the plant to actinic artificial light. The invention moreover relates to a method for growing a plant in at least partly conditioned manner, wherein actinic light is supplied to the plant and wherein a root temperature of a root system of the plant is maintained at a desired value.Description of the Related Art[0002]Such a system and such a method are applied on a significant scale in the glass horticulture in greenhouses. An artificial climate is created here in an at least substantially closed and conditioned environment b...

AI Technical Summary

Benefits of technology

[0007]The invention is based here on the insight that three factors are essentially responsible for a successful plant development, i.e. the photosynthesis, the sap flow in the plant pushed upwards under the influence of a prevailing root pressure, and the carbon dioxide assimilation through mainly the leaf system of the plant, and that these three factors must at all times be adapted to each other in order to actually realize an optimal plant growth. In addition to the root temperature and the entry of actinic light, a carbon dioxide assimilation management of the plant can also be controlled by providing the leaf heating means in the system according to the invention. Due to additional heating the stomata in the leaf will open further, so enhancing entry of carbon dioxide to the leaf and evaporation of moisture from the leaf. This latter is particularly important if a sap flow in the plant is stimulated by an increased root temperature, as this flow will have to exit via the same stomata. Conversely, the leaf temperature can be decreased at a lower sap flow in order to prevent undesired plant dessication. All in all, the most important climate parameters responsible for the development of the plant can thus be controlled so that an optimal efficiency can be realized in each of these components with a minimal energy consumption.

[0008]A particular embodiment of the system has the feature according to the invention that the lighting means are able and adapted to emit a lighting spectrum which can be adapted to an intended photosynthesis and / or mode of growth of the plant to be cultivated. The actinic light components necessary for the development of the plant can thus be supplied only in precisely sufficient intensity, while non-actinic components or an excess can be avoided as far as possible in order to limit the overall energy consumption of the system and / or possible harmful effect on the plant development.

[0010]The leaf heating means can be formed per se in various ways, although in a preferred embodiment the system according to the invention is characterized in that the leaf heating means comprise at least one heat source able and adapted to irradiate the leaf with infrared radiation. Other than heating means which, wholly or partially through guiding of an intervening medium, are capable of heat-exchanging contact with the leaf, such a heat source enters into heat-exchanging contact mainly through direct irradiation. Not only does this result in a highly effective and efficient heating of the leaf system, the intended temperature difference with the environment contributing toward a desired widening of the stomata is hereby also achieved in particularly effective manner. In a further preferred embodiment the system according to the invention is characterized here in that the lighting means and the heat source are accommodated in mutually separated fittings in order to thus exclude a possibly disruptive influence of an inevitable heat dissipation in the heat source itself from the conditioning sphere of the actinic light source.

Problems solved by technology

Classic glass horticulture does however also have drawbacks.

It costs energy to keep a greenhouse warm and, for some plants, lighted day and night.

Traditional greenhouses do after all require entry of sunlight and take up a relatively large amount of expensive land area in these areas, which could otherwise be employed for offices, house-building or infrastructure.

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